Your Welcome, when I converted my 81 over from the wait-forever to 7 second plugs I had a ride awakening...my car wouldn't start.
The diesel will start with one good glow plug, but when that goes even here in Georgia in the summer NADA bing Notta bang called a tow the first time. What I have come to realize is that they usually go bad one or two at a time, and the car will start on 3,2,1 but not on none.
When I tested the 3 and 4th plug and they didn't get warm, I replaced them and the car started better than it did, when I replaced the other two 1, and 2 it really rather started quickly and ran better cold.. Go figure... So I started to carry a spare couple of plugs and the wrenches to swap them (ok sockets 1/4 drive deep well and extension) in my glove box and when the car wouldn't start, that number 4 was the first one I changed..
What was really funny was the wait-for-ever ones I had originally lasted about 135K and a few years, and when I tested those, they were still good...I think it is the higher amperage that the 7 second ones use that makes them burn out 1-1.5 years....
Glad you got it sorted.